The noisy ceramic hip: is component malpositioning the cause?

Squeaking in large diameter ceramic-on-ceramic bearings in total hip arthroplasty

We analyzed the results of 206 consecutive total hip arthroplasties performed using large diameter ceramic-on-ceramic bearings. At an average follow-up of 28months, the mean Harris Hip Score improved from 54 to 92. Fifteen (7.3%) hips were noted to squeak. There was no significant difference between silent and squeaking hips with regards to age, weight, height, BMI, range of movement, femoral head diameter, leg length, and offset or center of rotation. No correlation was present between incidence of squeaking and increasing cup inclination and anteversion. 5.2% of cups orientated within Lewinnek's safe zone squeaked. No hips required revision for squeaking. While large diameter ceramic bearings may produce squeaking, our early results of surgery using large head ceramic bearings are encouraging. However, long-term follow-up is required.

Ceramic liner fracture and impingement in total hip arthroplasty

BACKGROUND

Ceramic-on-ceramic bearing surfaces were developed to provide an alternate to metal-on-polyethylene to decrease wear-induced osteolysis in total hip arthroplasty patients. In an effort to decrease the risk of ceramic acetabular component fracture or damage during implantation, a raised metal rim was added.

QUESTIONS/PURPOSES

How many fractures or impingements have occurred in our population of patients with ceramic liners with raised rims?

METHODS

With IRB-approved consent, a case series was reviewed from a single center registry and 4 of 169 patients were identified who had revision hip surgery with the ceramic liner with a raised metal rim: one for ceramic liner fracture and three for metallosis, pain, and squeaking. Implant alignment and operative findings were reviewed.

RESULTS

One ceramic liner fracture and three cases of metallosis from impingement of the femoral neck on the posterior elevated metal rim of the acetabular liner were observed at revision. The femoral neck in each patient had a divot that corresponded to a divot in the posterosuperior liner rim. Three of the four patients had audible squeaking or clicking prior to revision. A total of 3% of patients in this series had clinically significant impingement with this implant type.

CONCLUSION

Acoustic phenomenon in a ceramic on ceramic bearing surface should be investigated with a cross-table lateral radiograph to evaluate component position. If symptomatic impingement is demonstrated, revision should be considered to avoid failure from metallosis or fracture.

Comparison between 28 mm and 32 mm ceramic-on-ceramic bearings in total hip replacement

Large femoral heads have become popular in total hip replacement (THR) as a method of reducing the risk of dislocation. However, if large heads are used in ceramic-on-ceramic THR, the liner must be thinner, which may increase the risk of fracture. To compare the rates of ceramic fracture and dislocation between 28 mm and 32 mm ceramic heads, 120 hips in 109 patients (51 men and 58 women, mean age 49.2 years) were randomised to THR with either a 28 mm or a 32 mm ceramic articulation. A total of 57/60 hips assigned to the 28 mm group and 55/60 hips assigned to the 32 mm group were followed for at least five years. No ceramic component fractures occured in any patient in either group. There was one dislocation in the 32 mm group and none in the 28 mm group (p = 0.464). No hip had detectable wear, focal osteolysis or prosthetic loosening. In our small study the 32 mm ceramic articulation appeared to be safe in terms of ceramic liner fracture.

Cite this article: Bone Joint J 2014;96-B:1459–63.

Bearing surfaces in hip replacement - Evolution and likely future

Total hip arthroplasty has evolved from the first total hip arthroplasty in 1938, through the revolutionization of hip arthroplasty by principles of low friction arthroplasty introduced by Sir John Charnley in 1960s to the present state of the art implants and techniques. The main concern regarding failure of total hip arthroplasty has been the biological response to particulate polyethylene debris generated by conventional metal on polyethylene bearing surfaces leading to osteolysis and aseptic loosening of the prosthesis. Therefore, recent research has been focussing on alternative bearing surfaces to reduce the particulate debris generated. These bearing surfaces include ceramic-polyethylene, metal-metal as well as ceramic-ceramic articulations and have demonstrated lesser friction rates as well as significantly lower wear rates as compared to widely used metal on polyethylene surfaces. Clinical experience until now has shown that metal on metal articulations have significant safety concerns whereas metal-on-highly crosslinked polyethylene, ceramic on ceramic and ceramic on highly crosslinked polyethylene articulations have shown encouraging results to hold promise for wider use in younger and more active patients. This review article discusses positives and drawbacks of various bearing surfaces in current clinical use in total hip arthroplasty as well as briefly explores the newer technologies on the horizon which may even further decrease wear and improve total hip arthroplasty survivorship.

Meta-analysis of the Incidence and Risk Factors for Squeaking after Primary Ceramic-on-ceramic Total Hip Arthroplasty in Asian Patients

Purpose

The purpose of this study was to assess the squeaking incidence and risk factors after primary ceramic-on-ceramic total hip arthroplasty (THA) in Asian patients using meta-analysis.

Materials and Methods

We performed a meta-analysis of published data on the squeaking incidence and risk factors from 2000 to 2013. Eight studies in Asians were analyzed for both squeaking incidence and risk factors and 25 studies in Western patients were analyzed for squeaking incidence. The data collected were: patient factors, surgical factors and implantation factors.

Results

The overall incidence of hip squeaking was 2.7% in Asians and 3.1% in Westerners. This difference was not statistically significant. The only significant risk factor was an increase in the acetabular cup abduction angle. Of the factors, the cup abduction angle was the only significant risk factor for the occurrence rate of squeaking, and the occurrence rate tended to increase with increasing angle.

Conclusion

The incidence of squeaking in Asians after primary ceramic-on-ceramic THA is 2.7% and is similar to that in Westerners. The increased cup abduction angle is associated with squeaking; therefore, surgeons should be careful not to implant the cup at a too steep abduction angle.

Ceramic-on-ceramic total hip arthroplasty: is squeaking related to an inaccurate three-dimensional hip anatomy reconstruction?

Many factors were incriminated in the squeaking generation in ceramic-on-ceramic total hip arthroplasty (THA), including the cup positioning and design. However, the influence of the stem orientation has not been investigated and the true three-dimensional hip anatomy has never been compared to the contralateral healthy hip. Three patients, who underwent unilateral ceramic-on-ceramic THA, complained of squeaking. CT-scans were performed to compare the true three-dimensional hip anatomy to the contralateral healthy hip. All patients presented evidence of posterior neck-rim impingement with a two-fold increase in the global anteversion (above 75°) comparatively to the healthy hip. The excess of anteversion was on the cup side in 2 cases and on the stem side in 1 case. We conclude that squeaking in ceramic-on-ceramic THA could be related to a poor accuracy of 3D hip anatomy reconstruction which generated a posterior impingement and subsequent anterior edge loading because of excessive global anteversion.

An estimation of the incidence of squeaking and revision surgery for squeaking in ceramic-on-ceramic total hip replacement: a meta-analysis and report from the Australian Orthopaedic Association National Joint Registry

Squeaking arising from a ceramic-on-ceramic (CoC) total hip replacement (THR) may cause patient concern and in some cases causes patients to seek revision surgery. We performed a meta-analysis to determine the incidence of squeaking and the incidence of revision surgery for squeaking. A total of 43 studies including 16,828 CoC THR that reported squeaking, or revision for squeaking, were entered into the analysis. The incidence of squeaking was 4.2% and the incidence of revision for squeaking was 0.2%. The incidence of squeaking in patients receiving the Accolade femoral stem was 8.3%, and the incidence of revision for squeaking in these patients was 1.3%.

Ceramic liner fractures presenting as squeaking after primary total hip arthroplasty

BACKGROUND

Squeaking after ceramic-on-ceramic total hip arthroplasty is a relatively uncommon phenomenon. It usually does not require treatment in the absence of pain, mechanical symptoms, and/or relentless squeaking. The purpose of this investigation was to report on four patients who presented with hip pain and squeaking due to fractured ceramic liners after ceramic-on-ceramic total hip arthroplasty.

METHODS

Four patients with painful squeaking after ceramic-on-ceramic total hip arthroplasty were seen at our institution. One patient had a revision for suspected loosening and excessive anteversion of the cup noted on radiographs and magnetic resonance imaging (MRI). The remaining three patients had a revision for audible squeaking with progressive pain.

RESULTS

Intraoperatively, the ceramic liners of all four patients were fractured.

CONCLUSIONS

Squeaking after ceramic-on-ceramic total hip arthroplasty rarely is a functional issue. However, painful squeaking without notable trauma may indicate fracture of the ceramic liner. Painful squeaking is difficult to evaluate by conventional imaging. When painful squeaking occurs, exploration via surgical revision is recommended in selected patients, as ceramic liner fractures may go unnoticed on radiographs and/or MRI and thus their actual prevalence may be higher than estimated.

Squeaking: Current knowledge and how to avoid it

This review aims to update the reader with current thinking and research related to the well documented phenomenon of squeaking hip arthroplasties. The etiology of squeaking is multifactorial and still not well understood. We aim to share our own experience and views on the combination of factors we believe increases the likelihood of squeaking, along with mechanisms by which the sound may be generated. Recent published findings from other groups are summarized along with an appropriate management algorithm we recommend for this cohort of patients.

Alternative bearings in total hip arthroplasty in the young patient

Total hip arthroplasty is an effective treatment option for advanced hip arthritis in elderly patients. Studies in young patients have traditionally shown less durable results. With current implants, surgical technique, and cementless fixation methods, the durability of total hip arthroplasty may now be related to the wear performance of the bearing surfaces. To improve implant longevity, there are several bearing surface choices currently available for this demanding group of patients. Alternatives must be evaluated in terms of the risks and benefits associated with each articulation, and all new technologies must be carefully monitored over the long term.

Clinical failure analysis of contemporary ceramic-on-ceramic total hip replacements

The present study investigates the performance of ceramic-on-ceramic total hip replacements by combining a retrieval analysis with a survivorship analysis to elucidate mechanisms that led to clinical failure. Semiquantitative surface damage assessment, contact profilometry, contour measurements, and scanning electron microscopy were performed to characterize the types and quantify the extent of surface damage on the retrieved ceramic components. The implantation period was positively correlated with both damage scores of the femoral heads (R = 0.573, p < 0.001) and the acetabular cups (R = 0.592, p < 0.001). Increased maximal out-of-roundness values of the femoral heads correlated with both increased metal transfer damage score (R = 0.384, p = 0.023) and increased stripe damage score (R = 0.729, p ≤ 0.001) of the acetabular liners. The damage rate (damage score/year) for both the retrieved heads and acetabular liners was at least 2.2-fold greater at inclination angles of >45° than the damage rate at inclination angles of ≤45°. For the retrieved femoral heads only, the linear wear rate of 25.5 ± 21.3 µm/year at inclination angles of >45° was 6-fold greater than the linear wear rate of 4.2 ± 2.3 µm/year at inclination angles of ≤45°. Metal transfer on the ceramic bearing surface could possibly contribute to fluid-film starvation and, in combination with an increased inclination angle, may facilitate an adhesive wear mechanism associated with stripe surface damage. At our institution, the clinical survivorship of ceramic-on-ceramic total hip replacements was 98.9% (a total of 9 out of 815 patients were revised within 10 years after total hip arthroplasty) with revision as the end point, suggesting their safe use in younger patients.

Can squeaking with ceramic-on-ceramic hip articulations in total hip arthroplasty be avoided?

Squeaking is a recognized complication of total hip arthroplasty with ceramic on ceramic bearings but the etiology has not been well identified. We evaluated 183 hips in 148 patients who had undergone ceramic-on-ceramic noncemented total hip arthroplasties at one center between 1997-2007 by standardized telephone interviews and radiographic review. Audible squeaking was reported from 22 hips (12% of 183) of 19 patients. Prevalence of squeaking was associated with younger age; obesity; lateralized cup position; use of beta titanium alloy femoral components and shortened head length options; and higher reported activity level, greater pain, and decreased satisfaction at the time of the interview. Squeaking was described as having little personal significance by most patients. Squeaking might be preventable in part through medialization of the acetabular cup and avoidance of the use of shortened femoral necks.

The incidence of noise generation arising from the large-diameter Delta Motion ceramic total hip bearing

Noise generation has been reported with ceramic-on-ceramic articulations in total hip replacement (THR). This study evaluated 208 consecutive Delta Motion THRs at a mean follow-up of 21 months (12 to 35). There were 141 women and 67 men with a mean age of 59 years (22 to 84). Patients were reviewed clinically and radiologically, and the incidence of noise was determined using a newly described assessment method. Noise production was examined against range of movement, ligamentous laxity, patient-reported outcome scores, activity level and orientation of the acetabular component. There were 143 silent hips (69%), 22 (11%) with noises other than squeaking, 17 (8%) with unreproducible squeaking and 26 (13%) with reproducible squeaking. Hips with reproducible squeaking had a greater mean range of movement (p < 0.001) and mean ligament laxity (p = 0.004), smaller median head size (p = 0.01) and decreased mean acetabular component inclination (p = 0.02) and anteversion angle (p = 0.02) compared with the other groups. There was no relationship between squeaking and age (p = 0.13), height (p = 0.263), weight (p = 0.333), body mass index (p = 0.643), gender (p = 0.07) or patient outcome score (p = 0.422). There were no revisions during follow-up. Despite the surprisingly high incidence of squeaking, all patients remain satisfied with their hip replacement.

The natural history of ceramic-on-ceramic prosthetic hip squeak and its impact on patients

BACKGROUND

Ceramic-on-ceramic (CoC) total hip arthroplasty (THA) has been scrutinised for a high incidence of post-operative squeak. The psychological and social consequences, and subsequent request for revision surgery are not well documented.

METHODS

Seventy consecutive primary CoC THA operated on by a single surgeon at a single institution were enroled and followed for an average 7.1 years. Information was obtained from routine post-operative review, medical records, mailed questionnaire and periodic phone interview.

RESULTS

Of 70 THA, 69 were available for follow-up. Seventeen (24.6 %) reported at least one instance of squeak, occurring on average 34.2 months post-operatively. Five (7.5 %) recalled being warned preoperatively of squeak as a potential complication. Six reported infrequent squeak and 11 frequent squeak. Ten were concerned, reporting embarrassment, harassment and anxiety regarding the longevity of their THA. One patient was planning revision surgery.

DISCUSSION

This study demonstrates the highest published prevalence of squeaking CoC THA and highlights the importance of warning patients of this potential complication.

Ceramic-on-ceramic total hip arthroplasty: incidence and risk factors of bearing surface-related noises in 125 patients

The ceramic-on-ceramic bearing surface has high wear resistance and good biocompatibility in total hip arthroplasty (THA). However, the postoperative noise problem has been an important issue. The purpose of this retrospective study was to determine the incidence and risk factors of bearing surface-related noises in patients with third-generation ceramic-on-ceramic THAs. One hundred twenty-five patients (143 hips) with ceramic-on-ceramic THAs were included in the study and followed to obtain noise and functional results. Patient factors, including sex, age, height, weight, body mass index, diagnosis, and postoperative range of motion, and surgical factors, including cup inclination, ceramic head size and length, and size of cup related to noises, were recorded. Mean follow-up was 4.2 years (range, 2-10 years). Mean Harris Hip Score was 94 points (range, 68-100 points) at latest follow-up. One (0.8%) patient had radiological evidence of osteolysis, and 4 (3.2%) patients had hip dislocation. No hip sustained a fracture of the ceramic component. Eight (6.4%) patients developed noise at their hips, including clicking in 4, grinding in 2, and snapping in 2. No patient developed squeaking hips or underwent revision surgery because of noisy hips. Younger patients (P=.01), a diagnosis of osteonecrosis (P=.014), a 28-mm ceramic head (P=.042), and a higher hip range of motion postoperatively (P=.001) were related to noise in ceramic-on-ceramic THAs. The study showed third-generation ceramic-on-ceramic THAs had a low incidence of noise problems. However, long-term follow-up is necessary to determine the clinical relevance.

A mid-term analysis suggests ceramic on ceramic hip arthroplasty is durable with minimal wear and low risk of squeak

BACKGROUND

The incidence of hip replacements in the younger patient is ever increasing. With this in mind, improving the longevity of hip arthroplasties is paramount. Alumina ceramic is a promising bearing surface due to its low wear rate and biological inertness.

PURPOSE

This study aims to review our experience with ceramic-on-ceramic total hip arthroplasty, reporting on the need for revision as well as the cause of failure. Our secondary purpose is to review our experience with the phenomenon of squeaking analysing and its effect on clinical outcome with specific emphasis on component positioning. Also reported are the results of our retrieval analysis of explanted components documenting the wear rate and our analysis of strip wear.

METHODS

A consecutive series of 301 primary cementless alumina-on-alumina total hip arthroplasties at a minimum of 10 years follow-up was reviewed. These arthroplasties all had third-generation ceramic-on-ceramic bearings performed through a posterior approach with repair of capsule and external rotators to bone. We analysed hips both clinically and radiographically. Analysis of wear in 62 ceramic bearings was performed using a Roundtest RA300 machine (Mitutoyo; Andover, UK), which has an accuracy of 0.01 μm.

RESULTS

Overall, the survival rate of the implants was 98% at 10 years. No ceramic fractures were encountered in this study. Seventy-four patients reported squeaking hips, and two cases were revised due to squeaking (0.6%). No failures were related to bearing wear.

CONCLUSIONS

We believe that ceramic-on-ceramic is a safe bearing coupling with excellent survivorship at 10 years.

Metal-on-Metal Bearing: Is This the End of the Line? We Do Not Think So

BACKGROUND

Recent studies have recommended the discontinuation of metal-on-metal (MoM) components in total hip arthroplasty (THA) because of adverse effects reported with large-diameter MoM THA. This is despite favorable long-term results observed with 28 and 32 mm MoM bearings.

QUESTIONS/PURPOSES

The aim of this study was to assess the value of calls for an end to MoM bearings as THA components. Specifically, we wish to address the risks associated with MoM bearings including adverse soft tissue reactions, metal ion release, and carcinogenic risk.

METHODS

The study evaluates the arguments in the literature reporting on MoM (adverse soft tissue reactions, metal ion release, and carcinogenic risk) and the experience of the current authors who re-introduced these bearings in 1995. They are balanced by a benefit-risk review of the literature and the authors' experience with MoM use.

RESULTS

Adverse reactions to metallic debris as well as metal ion release are predictable and can be prevented by adequate design (arc of coverage, clearance), metallurgy (forged instead of cast alloy, high-carbide content), and appropriate component orientation. There is no scientific evidence that carcinogenicity is increased in subjects with MoM hip prostheses. MoM articulations appear to be attractive allowing safe hip resurfacing, decreasing the risk of THA revision in active patients, and providing secure THA fixation with cement in cages in severely deformed hips. MoM bearings in women of child-bearing age are controversial, but long-term data on metallic devices in adolescents undergoing spinal surgery seem reassuring.

DISCUSSION

Adequate selection of MoM articulations ensures their safe use. These articulations are sensitive to orientation. Fifteen years of safe experience with 28- and 32-mm bearings of forged alloy and high-carbide content is the main reason for retaining them in primary and revision THA.

Ceramic-Ceramic Bearing: Too Unpredictable to Use it Regularly

BACKGROUND

Ceramic-on-ceramic (CoC) bearings have excellent tribologic properties because of the smoothness, hardness, and wettability of the material. Therefore, their use has been proposed in younger, active patients who may wear out a traditional metal-on-polyethylene bearing. The same material properties that are beneficial to tribology may also create problems, however. For example, squeaking and fracture of the bearing materials have been reported to occur.

PURPOSE

The purpose of this paper was to investigate the literature reporting the complications of ceramic bearings and attempt to provide insight into their implications.

METHODS

The US National Library of Medicine Database (PubMed) was searched using the terms "ceramic-ceramic total hip replacement," "complications," "squeaking," and "fracture." Only clinical studies with a clear reporting of the incidence of these complications were included.

RESULTS

The literature reports that squeaking of the CoC bearing occurs in a certain percentage of patients and is likely indicative of edge loading and excessive wear. Other factors, such as patient height, weight, range of motion, and implant design, may contribute to the propensity for squeaking. Fracture is a unique risk of the CoC articulation that requires revision surgery. Though improvements in manufacturing techniques have reduced the fracture risk to a very low percentage, the ceramic material remains susceptible to this complication by impingement and component malposition.

CONCLUSIONS

Because of these possible negative outcomes associated with the ceramic material, the CoC bearing is too unpredictable to use regularly, and its use should be limited to patients who would benefit the most from it.

Concomitant evolution of wear and squeaking in dual-severity, lubricated wear testing of ceramic-on-ceramic hip prostheses

Ceramic-on-ceramic (CoC) hip bearings were tested in short-term wear tests with a systematically varied contact force. Continuous vibration and intermittent surface roughness measurements were obtained to elucidate potential causes of in vivo hip joint squeaking. The three-phase test comprised alternating cycles of edge loading (EL) and concentric articulation (CA), always using ample serum lubricant. A 50,000-cycle wear trial in which the contact force during CA was distant from the head's wear patch yielded no squeaking and practically no liner roughening. In 10-cycle trials of an edge-worn head coupled with a pristine liner, the contact force was varied in magnitude and point of application; immediate, recurrent squeaking occurred only when the contact force exceeded a critical threshold value and was centered upon the head's wear patch. In a 27,000-cycle wear trial with the contact force applied near the margin of the head's wear patch, recurrent squeaking emerged progressively as the liner's inner surface was roughened via its articulation with the worn portion of the head. The results reveal key conditions that yield recurrent squeaking in vitro in various scenarios without resorting to implausible dry conditions. A fundamental theory explains that hip squeaking is induced by myriad stress waves emanating from asperity collisions; yet, the root cause is edge loading.

No significant squeaking in total hip arthroplasty: a series of 413 hips in the Asian people

Some studies have reported the presence of audible squeaking in ceramic-on-ceramic total hip arthroplasty (THA), and several factors such as implant malposition or poor soft tissue recovery have been described as the cause. Our purpose was to determine the squeaking rate in the Asian population with a consecutive series of ceramic-on-ceramic THA. From 2003 to 2009, 413 THAs were performed by a single surgeon using a minimally invasive modified anterior-lateral approach. Using both questionnaire and physical examination, no squeaking was identified in any cases with a minimum of 2-year follow-up. Complications occurred in 4 patients. The results of this study suggested squeaking phenomenon after ceramic-on-ceramic THA may be eliminated.

Development of ceramic-on-ceramic implants for total hip arthroplasty

Over the past three decades, alumina ceramic, now in its third/fourth generation, has been markedly improved in terms of its mechanical properties, including purity, grain microstructure, and burst strength. In the clinic, it is particularly suitable for young and for very active patients. This paper discusses the development and characteristics of different kinds of ceramics. In addition, ceramics in the third/fourth generation which are used in total hip arthroplasty clinically are reviewed in detail.

Third-generation ceramic-on-ceramic total hip arthroplasty in patients younger than 30 years with osteonecrosis of femoral head

The purpose of this study was to evaluate the functional and radiographic results of patients younger than 30 years who underwent cementless third-generation ceramic-on-ceramic total hip arthroplasty for osteonecrosis of the femoral head. Forty-one patients (56 hips) with a minimum follow-up of 6 years were included. In all cases, third-generation ceramic-on-ceramic articulation was used. Average Harris Hip Scores improved from 52.9 preoperatively to 98.2, and Western Ontario and McMaster Universities Osteoarthritis Index score, from 95.2 to 25.2. Thirty-nine patients returned to their normal occupations. No aseptic loosening or osteolysis was observed. Total hip arthroplasty performed using third-generation ceramic-on-ceramic bearings for osteonecrosis of femoral head was found to provide satisfactory clinical and radiologic results, especially in active, young patients.

Hip squeaking: a 10-year follow-up study

The aim of the study was to analyze the incidence of squeaking with ceramic-on-ceramic total hip arthroplasty (THA) after 10 years of follow-up and the potential complications that could occur related to this phenomenon. One hundred THAs implanted between November 1999 and December 2000 were evaluated. Incidence of squeaking was investigated clinically with a questionnaire. Implant positioning was analyzed on x-rays and computer tomography. Of the 100 THAs, 5 patients presented with squeaking. All of them were active, sporty, and heavy men. Functional scores were comparable with nonsqueaking patients. There was no malpositioning on the x-ray analysis, no wear, and no loosening. We could not demonstrate any relation between squeaking and ceramic fracture. Squeaking noise appeared at a mean of 66 months postsurgery. It appears to be an isolated phenomenon without any consequences at 10-year follow-up.

Squeaking after third-generation ceramic-on-ceramic total hip arthroplasty

We retrospectively reviewed records of 1002 patients who underwent a third-generation ceramic-on-ceramic total hip arthroplasty. Fifteen patients complained of squeaking, at any time after their arthroplasty. Of these 15 patients, 14 were evaluated clinically and radiologically. These 14 patients were found to have significantly higher mean body mass index of 25.8 kg/m(2) as compared with all the other patients who did not complain of squeaking (mean, 23.7 kg/m(2)) (P = .022). The acetabular opening angle was significantly lower (mean, 34°) than a matched control group (mean, 38°) (P = .016). Limb length shortening of more than 5 mm was observed in 12 (85.7%) of the 14 patients as compared with only 4 (28.6%) of 14 patients in the matched control group. Flexion and sitting cross legged were identified as the movements, which most commonly (11/12) resulted in squeaking. The incidence of squeaking was found to be low (1.5%), and we identified high body mass index, decreased acetabular opening angle, and limb length shortening as factors associated with squeaking.

Retrieval analysis of squeaking ceramic implants: are there related specific features?

INTRODUCTION

Ceramic-on-ceramic total hip arthroplasty is routinely used for young and active patients with end stage of hip osteoarthritis. However, squeaking noise is a recently identified problem with such bearing surface. Many in vivo and in vitro studies have been conducted trying to find the potential causes of this phenomenon. However, we are not aware of any study analyzing retrieved ceramic implants for squeaking.

HYPOTHESIS

Our primary hypothesis was that the surface analysis of retrieved ceramic implants with squeaking would present interesting deteriorations that could explain the squeaking noise.

MATERIALS AND METHODS

Nine retrieved squeaking implants from ceramic-on-ceramic total hip arthroplasty that were retrieved for various reasons (two exclusively for squeaking, four for recurrent dislocation, one for aseptic loosening and two for instability) were analyzed. Implant positioning was calculated, macroscopic damages were noticed and microscopic roughness was analyzed. The retrieved implants were then tested on a hip simulator reproducing flexion/extension motions in several situations in lubricated and non-lubricated conditions in order to reproduce squeaking.

RESULTS

Five cups were considered with borderline insufficient anteversion. Gross impingement damage was visible on seven implants. All the retrieved heads had visible metal transfer on their surface. Eight implants had visible stripe wear. Microscopic analysis showed roughness higher than six microns on the retrieved heads. Squeaking was reproduced in vitro in dry conditions. In lubricated conditions, squeaking did not occur for the retrieved hips.

DISCUSSION

This retrieval analysis suggests that problems of cup orientation and design which can lead to impingement can generate lubrication problems because of metal transfer plus/minus stripe wear which is a common theme in ceramic-on-ceramic bearings that squeak.

Eleven- to 14-year follow-up results of cementless total hip arthroplasty using a third-generation alumina ceramic-on-ceramic bearing

To analyze long-term survivorship of cementless total hip arthroplasties (THAs) with the third-generation alumina ceramic-on-ceramic bearing, 100 consecutive THAs between 1996 and 1998 were reviewed. One cup and 2 stems were revised due to aseptic loosening. Another cup showed chipping of the acetabular liner at 8 years and required cup revision. The remaining hips showed stable bone ingrowth fixation with no osteolysis at the final follow-up. The 14-year survivorship as the end point of revision was 97.9% for the cup, 97.8% for the stem, and 95.7% for the overall implants, respectively. We conclude that cementless THA with the third-generation ceramic-on-ceramic hip bearing provided an excellent survivorship and eliminated periprosthetic osteolysis for 11 to 14 years.

A prospective randomised controlled trial comparing three alternative bearing surfaces in primary total hip replacement

The ideal bearing surface for young patients undergoing total hip replacement (THR) remains controversial. We report the five-year results of a randomised controlled trial comparing the clinical and radiological outcomes of 102 THRs in 91 patients who were <  65 years of age. These patients were randomised to receive a cobalt–chrome on ultra-high-molecular-weight polyethylene, cobalt–chrome on highly cross-linked polyethylene, or a ceramic-on-ceramic bearing. In all, 97 hip replacements in 87 patients were available for review at five years. Two hips had been revised, one for infection and one for peri-prosthetic fracture.

At the final follow-up there were no significant differences between the groups for the mean Western Ontario and McMaster Universities osteoarthritis index (pain, p = 0.543; function, p = 0.10; stiffness, p = 0.99), Short Form-12 (physical component, p = 0.878; mental component, p = 0.818) or Harris hip scores (p = 0.22). Radiological outcomes revealed no significant wear in the ceramic group.

Comparison of standard and highly cross-linked polyethylene, however, revealed an almost threefold difference in the mean annual linear wear rates (0.151 mm/year versus 0.059 mm/year, respectively) (p < 0.001).

Squeaking in third- and fourth-generation ceramic-on-ceramic total hip arthroplasty: meta-analysis and systematic review

Postoperative squeaking in ceramic-on-ceramic total hip arthroplasty is a recently emerging phenomenon. We performed a meta-analysis of published data to examine patient and procedural risk factors. Twelve studies (6137 patients, total) were analyzed, with 150 patients (2.4%) complaining of squeaking. The only significant patient risk factor was increasing body mass index (P = .03, n = 2957). There was no significance found with patient age, sex, height, weight, or procedural laterality for squeak incidence. For implant type, the presence of a Stryker Accolade femoral stem (beta-titanium; Stryker Orthopedics, Mahwah, NJ) was significantly found to increase squeak (P < .0001, n = 4654). The presence of a raised metallic lip on the acetabular component was not found to be associated with squeak. Acetabular cup position was also not found to have a significant bearing on the incidence of squeaking.

Spectral characterization of squeaking in ceramic-on-ceramic total hip arthroplasty: comparison of in vitro and in vivo values

Squeaking is a cause for concern in total hip arthroplasty (THA). However, the definition of this sound remains vague. Our goals were to characterize spectrally the squeaking in vitro under lubricated conditions and to compare the in vitro frequencies to in vivo frequencies. Four patients, who presented with a squeaking after ceramic-on-ceramic THA were investigated. In addition, 3 alumina ceramic 32 mm diameter components were tested in vitro under edge loading conditions using a friction simulator. Tests were conducted under lubricated conditions without and with the addition of a third body alumina particle. In vitro, no squeaking occurred under edge loading conditions. However, with the addition of a third body particle in the contact region, squeaking was obtained; the dominant frequency was 2.6 kHz. In vivo, the main recorded sound frequencies were: 2.3, 2.24, and 2.46 kHz for squeakers during walking and 1.45 kHz for a squeaker rising from a bent position. The in vivo recordings had a dominant frequency similar to, but slightly lower than, the in vitro values. Two types of squeaking were found in vivo and characterized spectrally. The rising squeaker had intermittent squeaking corresponding to a lower fundamental frequency compared to the walking squeakers. This finding suggests two different mechanism of squeaking.

Metal transfer on a ceramic head with a single rim contact

A notable feature of retrieved ceramic-on-ceramic hips is metal transfer on the femoral head, which is an important alteration of the bearing surface. This report documents metal transfer streaks on a ceramic femoral head resulting from discrete subluxations, which occurred intraoperatively during reduction and stability testing. An important implication is that metal transfer can occur whenever a femoral head is reduced into the liner during surgery or from in vivo subluxation/dislocation. If a ceramic liner is recessed below a raised metal rim, care should be taken to prevent head-to-rim contact during intraoperative reductions and stability testing. If metal transfer occurs during final surgical reduction of the hip, its presence may remain undetected, and detrimental effects are present from the time of surgery.

Retrieval analysis of squeaking alumina ceramic-on-ceramic bearings

This multicentre study analysed 12 alumina ceramic-on-ceramic components retrieved from squeaking total hip replacements after a mean of 23 months in situ (11 to 61). The rates and patterns of wear seen in these squeaking hips were compared with those seen in matched controls using retrieval data from 33 'silent' hip replacements with similar ceramic bearings. All 12 bearings showed evidence characteristic of edge-loading wear. The median rate of volumetric wear was 3.4 mm(3)/year for the acetabular component, 2.9 mm(3)/year on the femoral heads and 6.3 mm(3)/year for head and insert combined. This was up to 45 times greater than that of previously reported silent ceramic-on-ceramic retrievals. The rate of wear seen in ceramic components revised for squeaking hips appears to be much greater than in that seen in retrievals from 'silent' hips.

Mid-term results of third-generation alumina-on-alumina ceramic bearings in cementless total hip arthroplasty: a ten-year minimum follow-up

BACKGROUND

Alumina ceramic-on-ceramic bearings have gained popularity in hip arthroplasty because of their properties of low wear and chemical inertness. In a previous study, we reported the excellent clinical results in a series of cementless ceramic-on-ceramic primary total hip arthroplasties at a minimum of five years of follow-up. The purpose of the present study was to determine the results in the same patient cohort at a minimum of ten years of follow-up.

METHODS

A series of 301 consecutive primary cementless total hip arthroplasties was assessed clinically and radiographically. Clinical information was available for 244 hips in 227 surviving patients at a minimum of ten years of follow-up, and radiographic information was available for 184 hips in 172 patients.

RESULTS

Twenty-six (9.2%) of the patients had died of an unrelated cause and eight (2.7%) had undergone revision arthroplasty by the time of the latest follow-up. The average Harris hip score was 94 points, with 95% (232) of the patients having an excellent or good result and <4% (nine) having moderate residual pain. All radiographic assessments showed evidence of stable osseous ingrowth. Nine revisions had been performed, including four femoral component revisions due to periprosthetic fracture, one femoral revision due to aseptic loosening, one femoral revision secondary to a femoral shortening osteotomy for nerve palsy, two acetabular cup revisions due to psoas tendinitis, and a repeat revision in one of the patients with psoas tendinitis due to acetabular osteolysis. The overall survival rate of the implants was 98% (95% confidence interval, 94.2% to 99.6%) at ten years with revision for any reason as the end point.

CONCLUSIONS

The patients in our series had a good implant survival rate, good function, a low implant wear rate as reported in the previous study, and no further radiographic evidence of failure at ten years after cementless primary total hip arthroplasty with alumina ceramic-on-ceramic bearings.

Long-term results of 32-mm alumina-on-alumina THA for avascular necrosis of the femoral head

Background

Ceramic bearings in total hip arthroplasty (THA) have been introduced in clinical practice to minimize the problem of polyethylene particle–induced osteolysis. The aim of the study is to report the results of 68 consecutive alumina-on-alumina THAs done in 61 patients for avascular necrosis (AVN) of the femoral head.

Materials and methods

In all implants a press-fit cup was used; it was combined with a 32-mm alumina head and with titanium-alloy stems. The mean age at surgery was 50 years. At an average follow-up of 13 years two hips have been revised, one for periprosthetic infection and one for excessive abduction of the cup.

Results

No revision for aseptic loosening is recorded; one anatomical cementless femoral stem had radiological evidence of definite aseptic loosening. No dislocations occurred, and no osteolysis was observed.

Conclusions

The results support the application of alumina-alumina THA for long-lasting replacements.

Thin hard crest on the edge of ceramic acetabular liners accelerates wear in edge loading

Ceramic acetabular liners may exhibit a small, sharp crest-an artifact of discontinuous machining steps--at the junction between the concave spherical surface and the interior edge. On 3 ceramic liners, this crest was found to form a 9° to 11° deviation from tangency. Edge loading wear tests were conducted directly on this crest and on a smoother region of the edge. The crest elicited 2 to 15 times greater volumetric wear on the femoral head. The propensity of the crest to rapidly (<2000 wear cycles) cause elevated wear under low contact force (200 N) suggests that the crest artifact of prevailing machining protocols might be a root cause of stripe wear and squeaking in ceramic acetabular bearings.

State of the art in hard-on-hard bearings: how did we get here and what have we achieved?

Total hip arthroplasty has shown excellent results in decreasing pain and improving function in patients with degenerative disease of the hip. Improvements in prosthetic materials, designs and implant fixation have now resulted in wear of the bearing surface being the limitation of this technology, and a number of hard-on-hard couples have been introduced to address this concern. The purpose of this article is to review the origins, development, survival rates and potential advantages and disadvantages of the following hard-on-hard bearings for total hip arthroplasty: metal-on-metal standard total hip arthroplasty; metal-on-metal hip resurfacing arthroplasty, ceramic-on-ceramic total hip arthroplasty; and ceramic-on-metal bearings. Improvements in the manufacturing of metal-on-metal bearings over the past 50 years have resulted in implants that provide low wear rates and allow for the use of large femoral heads. However, concerns remain regarding elevated serum metal ion levels, potential teratogenic effects and potentially devastating adverse local tissue reactions, whose incidence and pathogenesis remains unclear. Modern total hip resurfacing has shown excellent outcomes over 10 years in the hands of experienced surgeons. Current ceramic-on-ceramic bearings have demonstrated excellent survival with exceptionally low wear rates and virtually no local adverse effects. Concerns remain for insertional chipping, in vivo fracture and the variable incidence of squeaking. Contemporary ceramic-on-metal interfaces are in the early stages of clinical use, with little data reported to date. Hard-on-hard bearings for total hip arthroplasty have improved dramatically over the past 50 years. As bearing designs continue to improve with new and modified materials and improved manufacturing techniques, it is likely that the use of hard-on-hard bearings will continue to increase, especially in young and active patients.

Is metal-on-metal squeaking related to acetabular angle of inclination?

BACKGROUND

Postoperative audible squeaking has been well documented in ceramic-on-ceramic hip prostheses, and several metal-on-metal (MOM) THA designs, specifically those used for large-head resurfacing and MOM polyethylene sandwich designs, and are attributed to different implant- and patient-specific factors. Current literature does not identify the incidence of squeaking in modular MOM THA or possible etiologic factors.

QUESTIONS/PURPOSES

Our purposes were to (1) identify the incidence of squeaking in modular MOM prostheses in THA; (2) determine whether males or females were more likely to have squeaking; and (3) determine whether the incidence of squeaking relates to acetabular inclination angle.

METHODS

We retrospectively reviewed the patient records and radiographs of 539 patients (542 hips) from three independent centers who underwent a MOM THA between February 2001 and December 2005. Demographic and implant factors were evaluated, including measurement of cup inclination angles. The minimum followup was 36 months (mean, 76 months; range, 36-119 months).

RESULTS

We identified squeaking in eight of the 542 hips (1.5%); five were in women and two were in men (one patient had bilateral squeaking). The time to onset of patient-reported audible squeaking averaged 23 months (range, 6-84 months). Squeaking was more likely to occur in women (six of eight hips). No hips with 45º or less acetabular inclination squeaked (291 hips); eight of 251 hips (3.2%) with inclination angles greater than 45º squeaked. Patients who reported squeaking had higher inclination angles than those who did not report squeaking.

CONCLUSIONS

Our observations suggest an increased frequency of squeaking in female patients and in patients with greater inclination angles with this MOM implant design.

A squeaky reputation: the problem may be design-dependent

BACKGROUND

Squeaking is reportedly a complication in patients having ceramic-on-ceramic total hip implants. The etiology remains unknown and multifactorial with recent studies suggesting a relationship between the audible squeak and implant design. When we evaluated our ceramic-on-ceramic cohort, we noticed squeaking primarily in patients receiving an acetabular system designed with an elevated titanium rim.

OBJECTIVES/PURPOSES

We therefore (1) determined the incidence of squeaking among four different ceramic-on-ceramic bearing surfaces used for THA at our institution; (2) evaluated the association between different acetabular designs and the incidence of squeaking; and (3) assessed other potential variables associated with squeaking.

METHODS

We retrospectively reviewed 1507 patients having a ceramic-on-ceramic THA between 2002 and 2009; we separately analyzed those receiving an acetabular system with and without an elevated titanium rim. Data were collected through phone-administered questionnaires and retrospective reviews of patient charts for intraoperative findings, followup reports, demographic information, and radiographic findings.

RESULTS

Squeaking occurred in 92 of the 1507 patients (6%). All 92 patients with squeaking received an elevated rim design (1291 patients) or an incidence of 7% with that design. We found no association between squeaking and any other examined factors.

CONCLUSION

Our findings complement the theory from in vitro studies suggesting that neck impingement on the elevated titanium rim is the probable cause of the increased frequency of squeaking with this design.

Occurrence of noise in alumina-on-alumina total hip arthroplasty. A survey on 284 consecutive hips

BACKGROUND

Alumina-on-alumina bearings have been accepted as a valuable alternative for young and active patients. Alumina fractures, and socket loosening were the main complications reported. But, with the increasing number of prostheses implanted, noise occurrence appeared as a new concern. The primary aim of the present study was to quantify the prevalence of noticing noise in a population having received alumina-on-alumina total hip arthroplasty as well as its eventual impact on outcome.

PATIENTS AND METHODS

Two hundred and eighty-four ceramic-on-ceramic hips were performed in 238 patients from January 2003 to December 2004. The average age was 52.4 ± 13.4 years (range, 13 to 74 years). All the hips received the same prosthesis (Ceraver-Osteal™) with alumina bearing components (Ceraver-Osteal™): 32 mm liners were used for cups of 50mm or larger and 28 mm liners for cups smaller than 48 mm; the minimal alumina thickness was 6mm. The acetabular component (Cerafit™) was hemispherical, coated with a hydroxyapatite layer and press-fit fixed. The stem (Cerafit™) was a straight tapered cementless stem, fully coated with a hydroxyapatite layer. Clearance between femoral head and liner was between 20 and 50 microns. A retrospective survey was conducted by an independent surgeon who did not participate to surgery in 2007. He conducted phone interviews of patients using a standard questionnaire. No suggestion was offered on how they could describe the noise and they felt free to use the word that they considered to be the most adapted. Satisfaction was evaluated. When the noise was present, X-rays were taken to assess if sign of bearings fracture was present.

RESULTS

Four patients (six hips) died of unrelated causes during the follow-up period. Three patients (three hips) live outside France and could not be followed (1.3%). Nine patients (10 hips) could not be traced and were considered lost to follow-up (3.8%). Two hundred and twenty-two patients with 265 hips, therefore, were included (nine using bearing components in 28 mm diameter and 265 in 32 mm). Twenty-eight hips experienced noise generation (10.6%). It was defined as a snap for six patients, as a cracking sound by six, as rustling by six patients, as a squeaking by seven patients (2.6%), a tinkling by two patients, one patient was unable to define the sound she felt. No factor related to the patient influenced the occurrence of noise. Twelve patients were dissatisfied with the result of their hip prosthesis, five of them experienced noise (41.7%); 210 were satisfied or very satisfied, 23 of them experiencing noise (11%); this difference was significant (P=0.002).

CONCLUSION

The origins of noise occurrence are unknown. Squeaking may be related to generation of stripe wear and absence of sufficient lubrication. Other types of noise can be due to microseparation, occult dislocation, impingement between the femoral neck and the acetabular rim.

LEVEL OF EVIDENCE

Level IV. Retrospective study.

Ceramic-on-ceramic total hip arthroplasty: incidence of instability and noise

BACKGROUND

Alternative bearing materials in THA have been developed to reduce the incidence of osteolysis. Alumina-on-alumina bearings exhibit extremely low wear rates in vitro, but concerns exist regarding component impingement with the potential for dislocation and the occurrence of noise.

QUESTIONS/PURPOSES

We determined generation of squeaking and the relationship between squeaking and component position.

METHODS

We prospectively entered 436 alumina-on-alumina, cementless, primary THAs in 364 patients into our institutional database. All procedures were performed with the same surgical technique and the same implant. We obtained Harris Hip scores and a noise questionnaire and assessed radiographic component position and loosening. We determined the difference in abduction angle between squeakers and nonsqueakers. Minimum followup was 2 years (average, 3.5 years; range, 2.0-6.2 years).

RESULTS

The mean Harris hip score increased from 51.9 preoperatively to 94.4 at latest followup. Six hips underwent reoperation: four hips (1.1%) for dislocation and two (0.53%) for periprosthetic fracture after trauma. The incidence of noise of any type was 11%, with the most common type of noise being clicking or snapping. Squeaking was reported by 1.9% of patients, with no patient being revised for this phenomenon. We found no association between component position and squeaking.

CONCLUSIONS

At average 3 years followup, 98% of ceramic-on-ceramic THAs did not require a revision, with 1.1% of hips having been revised for dislocation. Fewer than 2% of patients reported hearing an audible squeak, with no association found between component position and squeaking.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Squeaking sound in total hip arthroplasty using ceramic-on-ceramic bearing surfaces

PURPOSE

To evaluate the causes and frequency of the squeaking sound in ceramic-on-ceramic THA.

MATERIALS AND METHODS

This study included 61 hips of 50 patients who underwent ceramic-on-ceramic THA in our hospital from March 1999 to April 2005. The average age at the time of operation was 57.6 years. The average duration of follow-up was 69.5 months. Three different acetabular components were used: Osteonics (Stryker, USA: 24 cases), Bicontact (Aesculap, Germany: 27 cases) and ABG (Howmedica, UK: 10 cases).

RESULTS

Fourteen (22.9%) of the 61 cases had a squeaking sound, and this sound started a mean of 47.57 months after the operation. Except in one case, the squeaking sound remained until the last follow-up. There was no difference in acetabular component position between the squeaking and nonsqueaking groups. The squeaking sound was found to be related to the BMI (body mass index) and cup design. It occurred frequently in patients with high BMI who had received a total hip arthroplasty using an Osteonics cup. Among 11 of the patients, squeaking occurred while squatting, and in 3 patients while walking. Six patients suffered from mild restrictions on their activities of daily living, and 8 had more than moderate restrictions with squeaking sounds.

CONCLUSION

A squeaking sound in THA using ceramic-on-ceramic surfaces is not a rare complication, and often affects the patient's behavior.

Incidence and factors associated with squeaking in alumina-on-alumina THA

BACKGROUND

The alumina-on-alumina bearing surface, which has a high wear resistance and a good biocompatibility, is widely used in THA but recently has been associated with squeaking. While various authors have reported factors associated with squeaking, they remain poorly understood.

QUESTIONS/PURPOSES

To contribute to the debate on squeaking we therefore asked the following questions: (1) What is the incidence of squeaking in alumina-on-alumina THA? (2) What factors are associated with squeaking in alumina bearings in our practice?

METHODS

We retrospectively reviewed 168 patients (173 hips) who had primary alumina-on-alumina THAs. The mean age of the patients was 53 years (range, 18 to 81 years). Minimum followup was 5.6 years (average, 7.3 years; range, 5.6-9.4 years). All patients were evaluated clinically and radiographically with attention to periprosthetic osteolysis, squeaking, and ceramic fracture. When the patient reported squeaking, we determined the onset, reproducibility, and activities associated with the squeaking. We recorded patient (gender, age, height, weight, and body mass index) and surgical factors (abduction angle of cup, size and length of ceramic head component, and diameter of cup in the implant).

RESULTS

Eight of the 168 patients (5%) had squeaking hips. Squeaking was more common in males and in those with large ceramic heads. There were no complications or revisions in the squeaking group. One ceramic liner fracture was associated with trochanteric nonunion.

CONCLUSIONS

When recommending alumina-on-alumina bearing surfaces to patients they should be clearly informed of the possibility of squeaking. Patients with risk factors for squeaking should be followed at regular intervals.

Revision hip arthroplasty for ceramic-on-ceramic squeaking hips does not compromise the results

Squeaking is a complication that may occur after ceramic-on-ceramic total hip arthroplasty (THA) that can be intolerable enough for some patients to seek revision THA. This prospective case series of 11 hips is the first to report on the results of these patients. All patients underwent isolated head and liner exchange to a metal-on-highly cross-linked polyethylene using the direct lateral approach. Mean age was 45.5 years, and body mass index was 30.0 kg/m(2). Hips were revised at an average of 40.1 months postindex THA. Retrieval analysis showed 7 of 7 liners/heads with edge loading wear and 5 of 7 liners with signs of neck-rim impingement. Short Form-36 mental dimension, Western Ontario McMaster Osteoarthritis Index, and Harris Hip Score (HHS) showed a statistically significant improvement (P < .05). All squeaking was eliminated after revision THA. There were no morbidities or complications after the revision surgery rendering isolated head-and-liner exchange to a metal-on-highly cross-linked polyethylene a relatively benign procedure.